1. Field Of The Invention
This invention relates to fluid coupling and more particularly to an improved coupling device for facilitating the coupling of a hose for use under fluid pressure.
2. Prior Art Statement
Various types of fluid coupling devices have been proposed in the prior art for coupling a hose for transmitting a wide variety of gases and liquids with a solid suspended therein. Coupling devices have been utilized for coupling hydraulic fluids, liquids, semi-solids and the like. Among the most difficult materials to transmit through a fluid coupling device are high pressure fluids such as high pressure liquids and/or high pressure gases with the solid particulate material suspended therein. In the field of sand blasting, wet blasting and painting, the difficulties encountered with fluid couplings are particularly troublesome due to the abrasive quality of the sand blasting or wet blasting materials.
In a typical sand blasting operation, a high pressure air compressor forces particulate abrasive material in the form of sand particles through a hose to a nozzle whereat the fluid projects the abrasive particles to a surface for cleaning and removing undesirable surface material. In general, the hose interconnecting the high pressure air compressor and the nozzle is composed of a plurality of hose sections interconnected by hose couplings. In the past, the hose couplings were typically formed from a metallic material and interconnected the hose sections to form a fluid tight conduit between the high pressure air compressor and the sand blasting nozzle. Since the abrasive material was transmitted through the hose and couplings at a high rate, it was common for the hose to become abraded and fracture at a point particularly where the hose would undergo a small radius bend. In addition, the high velocity abrasive material would likewise abrade the couplings interconnecting the hose sections, thereby deteriorating the fluid tight seals in the coupling member. The deterioration of the fluid tight seal, typically an O-ring in the coupling member, would cause high pressure leaks which further increased the leak in the coupling member resulting in the failure of the coupling member. Accordingly, the coupling member would have to be replaced by a new coupling. It should be appreciated that a typical sand blasting operation incorporates a multitude of coupling members between the air compressor and the nozzle. The replacement of the coupling members caused a substantial downtime for the sand blasting operation, resulting in enormous expense in some situations, for example a ship located in a dry dock. The dry dock fees of large ships are very substantial and the failure of a low cost coupling member resulted in a very substantial loss in the overall cost of the sand blasting operation.
In my prior U.S. Pat. No. 4,666,193 issued May 19, 1987 I disclosed a novel pipe coupling incorporating an insert which provided a partial solution to the above problems of the prior art.
In my subsequent U.S. Pat. No. 4,666,188 issued May 19, 1987, I disclosed a superior coupling member made of a resilient plastic material which was suitable for use with high pressure fluids and/or liquids and specifically suitable for sand blasting and wet blasting operations. In this superior coupling member, the end of a first hose was abutted against an end of a second hose to provide a hose to hose coupling and to eliminate any metallic material interposed between the first and second hoses. This invention eliminated any contact of the abrasive material with any coupling material of the coupling members.
It is a primary object if the present invention to provide an improvement to my prior invention set forth in U.S. Pat. No. 4,666,188 which improvement is lower in cost and which is more convenient in the connection of a hose to the coupling member.
Another object of the present invention is to provide a coupling apparatus for coupling a first and a second hose comprising a first and a second coupling member having first and second coupling thread means enabling the first coupling member to be threadably engaged with the second threaded member.
Another object of the present invention is to provide a coupling apparatus for coupling a first and a second hose wherein the first and second coupling members are constructed of a resilient and deformable material for enabling radial expansion of the first and second coupling members upon the application of fluid pressure in combination with means for inhibiting the radial expansion of the second coupling member, whereby the radial expansion of the first coupling member within the second coupling member creates a fluid tight seal therebetween.
Another object of the present invention is to provide a coupling apparatus for coupling a first and a second hose including a locking pin to releasably inhibit relative rotation between the first and second coupling members.
Another object of the present invention is to provide a coupling apparatus for coupling a first and a second hose having a first and a second attachment member connected to the first and second hoses, respectively, with a flowable adhesive.
Another object of the present invention is to provide a coupling apparatus for coupling a first and a second hose, wherein the first and second hoses are secured to a first and a second attachment means and the first and second attachment means are secure to a first and a second coupling member of the coupling apparatus by linking thread means enabling the hose sections to be readily attached to the coupling apparatus.
Another object of the present invention is to provide a coupling apparatus for coupling a first and a second hose wherein the first and second coupling thread means have an integral number of turns for enabling the insertion of a first hose section between a second and third hose section while maintaining the preferred orientation of the first, second and third hose sections.
Another object of the present invention is to provide a coupling apparatus for coupling a first and a second hose which enables a hose to hose coupling such that the first and second coupling members are not exposed to the material internal the hose.
Another object of the present invention is to provide a coupling apparatus for coupling a first and a second hose wherein the first and second coupling members are constructed of a low cost polymeric material.
Another object of the present invention is to provide a coupling apparatus for coupling a first and a second hose which is lower in cost, more reliable, and provides easier replacement of the coupling member on a hose than heretofore known in the art.
The foregoing has outlined some of the more pertinent objects of the present invention. These objects should be construed to be merely illustrative of some of the more prominent features and applications of the invention. Many other beneficial results can be attained by applying the disclosed invention in a different manner or modifying the invention within the scope of the invention. Accordingly, other objects and a fuller understanding of the invention may be had by referring to the summary of the invention and the detailed description describing the preferred embodiment in addition to the scope of the invention defined by the claims taken in conjunction with the accompanying drawings.